Helleborus plant named ‘COSEH 6000’

ABSTRACT

A new and distinct cultivar of  Helleborus  plant named ‘COSEH 6000’, characterized by its upright to outwardly spreading and mounded plant habit; moderately vigorous to vigorous growth habit; dark green-colored leaves; freely flowering habit; dark greyed purple-colored flowers; and good garden performance.

Botanical designation: Helleborus x ericsmithii X Helleborus x hybridus.

Cultivar denomination: ‘COSEH 6000’.

CROSS-REFERENCED TO CLOSELY-RELATED APPLICATIONS

Title: Helleborus Plant Named ‘COSEH 6100’

Inventor/Applicant: Josef Heuger

Plant patent application Ser. No. 16/873,647

Title: Helleborus Plant Named ‘COSEH 6300’

Inventor/Applicant: Josef Heuger

Plant patent application Ser. No. 16/873,646

Title: Helleborus Plant Named ‘COSEH 7900’

Inventor/Applicant: Josef Heuger

Plant patent application Ser. No. 16/873,651

Title: Helleborus Plant Named ‘COSEH 8000’

Inventor/Applicant: Josef Heuger

Plant patent application Ser. No. 16/873,650

STATEMENT REGARDING PRIOR DISCLOSURES BY INVENTOR/APPLICANT

An European Community Plant Breeder's Rights application for the instant plant was filed by the Inventor/Applicant, Mr. Josef Heuger of Glandorf, Germany, on Jun. 6, 2019, application number 2019/1384. Foreign priority is not claimed to this application.

The Inventor/Applicant asserts that no publications nor advertisements relating to sales, offers for sale or public distribution occurred more than one year prior to the effective filing date of this application. Any information about the claimed plant would have been obtained from a direct or indirect disclosure from the Inventor or Applicant. Inventor/Applicant claims a prior art exemption under 35 U.S.C. 102(b)(1) for disclosure and/or sales prior to the filing date but less than one year prior to the effective filing date.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Helleborus plant, botanically known as Helleborus x ericsmithii X Helleborus x hybridus and hereinafter referred to by the name ‘COSEH 6000’.

The new Helleborus plant is a product of a planned breeding program conducted by the Inventor in Glandorf, Germany. The objective of the breeding program was to create new uniform Helleborus plants with unique and attractive plant habit, leaf and flower coloration and tolerance to biotic and abiotic stress.

The new Helleborus plant originated from a cross-pollination conducted by the Inventor in Glandorf, Germany in December, 2011 of a proprietary selection of Helleborus x ericsmithii identified as code number P840, not patented, as the female, or seed patent and an unnamed selection of Helleborus x hybridus, not patented, as the male, or pollen parent. The new Helleborus plant was discovered and selected by the Inventor as a single flowering plant from within the progeny of the stated cross-pollination grown in a controlled greenhouse environment in Glandorf, Germany in November, 2013.

Asexual reproduction of the new Helleborus plant by in vitro axillary meristem culture in a controlled environment in Glandorf, Germany since March, 2014 has shown that the unique features of this new Helleborus plant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Helleborus have not been observed under all possible combinations of environmental conditions and cultural practices. The phenotype may vary somewhat with variations in environmental conditions such as temperature and light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘COSEH 6000’. These characteristics in combination distinguish ‘COSEH 6000’ as a new and distinct Helleborus plant:

-   -   1. Upright to outwardly spreading and mounded plant habit.     -   2. Moderately vigorous to vigorous growth habit.     -   3. Dark green-colored leaves.     -   4. Freely flowering habit.     -   5. Dark greyed purple-colored flowers.     -   6. Good garden performance.

Plants of the new Helleborus differ from plants of the female parent selection in the following characteristics:

-   -   1. Plants of the new Helleborus are more compact than and not as         vigorous as plants of the female parent selection.     -   2. Flowers of plants of the new Helleborus are darker greyed         purple in color than flowers of plants of the female parent         selection.

Plants of the new Helleborus differ from plants of the male parent selection in the following characteristics:

-   -   1. Leaves of plants of the new Helleborus are darker green in         color than leaves of plants of the male parent selection.     -   2. Leaf venation of plants of the new Helleborus is more visible         than leaf venation of plants of the male parent selection.

Plants of the new Helleborus can be compared to plants of Helleborus x ericsmithii X Helleborus x hybridus ‘COSEH 6100’, disclosed in a U.S. Plant Patent application filed concurrently. Plants of the new Helleborus differ primarily from plants of ‘COSEH 6100’ in flower color as plants of the new Helleborus have dark greyed purple-colored flowers whereas plants of ‘COSEH 6100’ have greyed purple to greyed red purple-colored flowers.

Plants of the new Helleborus can be compared to plants of Helleborus x ericsmithii X Helleborus x hybridus ‘COSEH 6300’, disclosed in a U.S. Plant Patent application filed concurrently. Plants of the new Helleborus differ primarily from plants of ‘COSEH 6300’ in flower color as plants of the new Helleborus have dark greyed purple-colored flowers whereas plants of ‘COSEH 6300’ have yellow green to greenish white-colored flowers with red purple to greyed purple-colored margins.

Plants of the new Helleborus can be compared to plants of Helleborus x ericsmithii X Helleborus x hybridus ‘COSEH 7900’, disclosed in a U.S. Plant Patent application filed concurrently. Plants of the new Helleborus differ primarily from plants of ‘COSEH 7900’ in flower color as plants of the new Helleborus have darker greyed purple-colored flowers than plants of ‘COSEH 7900’.

Plants of the new Helleborus can be compared to plants of Helleborus x ericsmithii X Helleborus x hybridus ‘COSEH 8000’, disclosed in a U.S. Plant Patent application filed concurrently. Plants of the new Helleborus differ primarily from plants of ‘COSEH 8000’ in flower color as plants of the new Helleborus have dark greyed purple-colored flowers whereas plants of ‘COSEH 8000’ have greyed purple to dark purple-colored flowers.

Plants of the new Helleborus can also be compared to plants of Helleborus x ericsmithii X Helleborus x hybridus ‘LEM 100’, disclosed in U.S. Plant Pat. No. 25,646. In side-by-side comparisons, plants of the new Helleborus differ primarily from plants of ‘LEM 100’ in the following characteristics:

-   -   1. Plants of the new Helleborus are more vigorous than plants of         ‘LEM 100’.     -   2. Plants of the new Helleborus have smaller flowers than plants         of ‘LEM 100’.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the overall appearance of the new Helleborus plant showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photographs may differ slightly from the color values cited in the detailed botanical description which accurately describe the colors of the new Helleborus plant.

The photograph on the first sheet (FIG. 1 of 2) is a side perspective view of a typical flowering plant of ‘COSEH 6000’ grown in a container.

The photograph on the second sheet (FIG. 2 of 2) is a close-up view of a typical flower of ‘COSEH 6000’.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photographs and following observations, measurements and values describe plants grown during March in 17-cm containers in a glass-covered greenhouse in Glandorf, Germany and under cultural practices typical of commercial Helleborus production. During the production of the plants, day temperatures ranged from 12° C. to 32° C. and night temperatures ranged from 5° C. to 12° C. Plants were four months old when the photographs and the description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 2015 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical classification: Helleborus x ericsmithii X Helleborus x     hybridus ‘COSEH 6000’. -   Parentage:     -   -   Female, or seed, parent.—Proprietary selection of Helleborus             x ericsmithii disclosed as code number P840, not patented.         -   Male, or pollen, parent.—Unnamed selection of Helleborus x             hybridus, not patented. -   Propagation:     -   -   Type.—In vitro axillary meristem culture.         -   Time to initiate roots, winter.—About 55 days at             temperatures about 12° C.         -   Time to produce a rooted young plant, winter.—About 170 days             at temperatures ranging from 4° C. to 15° C.         -   Root description.—Thick to thin, fleshy; typically white to             brown in color, actual color of the roots is dependent on             substrate composition, water quality, fertilizer type and             formulation, substrate temperature and physiological age of             roots.         -   Rooting habit.—Low branching; sparse. -   Plant description:     -   -   Plant and growth habit.—Herbaceous perennial; upright and             mounding plant habit with flowers held within and above the             foliar plane; plant shape, roughly flattened globular;             moderately vigorous to vigorous growth habit and moderate to             rapid growth rate.         -   Plant height, soil level to top of foliar plane.—About 28             cm.         -   Plant height, soil level to top of flowers.—About 47.3 cm.         -   Plant diameter (area of spread).—About 66.5 cm. -   Leaf description:     -   -   Arrangement.—Leaves arranged in a basal rosette; leaves             palmately compound with typically five leaflets per leaf.         -   Leaf length.—About 17.3 cm.         -   Leaf width.—About 19.6 cm.         -   Leaflet length.—About 11.6 cm.         -   Leaflet width.—About 7.1 cm.         -   Leaf shape.—Palmate; reniform to orbicular in outline.         -   Leaflet shape.—Ovate to elliptic and obovate.         -   Leaflet apex.—Acute.         -   Leaflet base.—Attenuate.         -   Leaflet margin.—Serrate; coarsely undulate.         -   Leaflet texture and luster, upper and lower             surfaces.—Smooth, glabrous; leathery; slightly glossy.         -   Leaflet venation pattern.—Pinnate.         -   Leaflet color.—Developing leaflets, upper surface: Close to             NN137C; midvein proximally, tinged with close to N186C.             Developing leaflets, lower surface: Slightly darker than             N186C. Fully developed leaflets, upper surface: Slightly             darker than between 147A and N189A; venation, close to 143B             and proximally, close to 187A. Fully developed leaflets,             lower surface: Close to 148B moderately tinged with close to             N186C; venation, close to 187A.         -   Petioles.—Length: About 17.7 cm. Diameter: About 7 mm to             8 mm. Strength: Strong. Texture and luster, upper and lower             surfaces: Smooth, glabrous; moderately glossy. Color, upper             and lower surfaces: Close to 147D heavily covered with fine             dots, close to 187A to 187B. -   Flower description:     -   -   Flower shape and habit.—Rotate flowers; flowers moderately             cupped; arranged in panicles; freely flowering habit with             about seven flowers per inflorescence and about 77 flowers             developing per plant; flowers face mostly outwardly to             slightly nodding.         -   Fragrance.—None detected.         -   Natural flowering season.—Plants begin flowering about ten             months after planting; plants flower naturally from winter             into the late winter in Germany.         -   Flower longevity on the plant.—About ten days; sepals             persistent, other flower parts are not persistent.         -   Flower buds.—Length: About 2.3 cm. Diameter: About 1.6 cm.             Shape: Broadly ovate. Texture and luster: Smooth, glabrous;             slightly glossy. Color: Close to between 59B and N77B;             venation, close to 187B.         -   Inflorescence height (including peduncle).—About 48 cm.         -   Inflorescence diameter.—About 22.6 cm.         -   Flower diameter.—About 6.2 cm by 6.2 cm.         -   Flower depth (height).—About 2.3 cm.         -   Petals.—All petals are transformed into nectaries.         -   Sepals.—Quantity and arrangement: About five, arranged in a             single whorl. Length: About 3.5 cm. Width: About 3.2 cm.             Shape: Broadly ovate, slightly concave. Apex: Obtuse. Base:             Truncate to broadly cuneate. Margin: Entire; not undulate.             Texture and luster, upper and lower surfaces: Smooth,             glabrous; matte. Color: When opening, upper surface: Close             to 183D; proximally, flushed with close to lighter than             148D; venation, similar to lamina. When opening, lower             surface: Close to between 59A and 183B; proximally, slightly             tinged with close to lighter than 148D; venation, close to             187B. Fully opened, upper surface: Close to 185D moderately             tinged with close to lighter than 177D; with development,             color becoming closer to N186C moderately tinged with close             to 200C; venation, similar to lamina. Fully opened, lower             surface: Close to between 59A and 187B; with development,             color becoming closer to N186C fading lighter towards the             base to close to N186D; venation, close to 187A.         -   Flower bracts.—Quantity per flower: Typically one or two.             Length: About 4.2 cm. Width: About 2.8 cm. Shape: Ovate.             Apex: Acute. Base: Truncate. Margin: Sparsely and finely             serrate; slightly undulate. Color, upper surface: Slightly             darker than between NN137A and 147A; venation, similar to             lamina. Color, lower surface: Slightly darker than N186C;             venation, similar to lamina.         -   Peduncles.—Length: About 40.5 cm. Diameter: About 1 cm.             Aspect: About 20° from vertical. Strength: Strong. Texture             and luster: Smooth, glabrous; moderately glossy. Color:             Close to 150D, heavily covered with fine dots, close to 187B             to 187C.         -   Pedicels.—Length: About 2.2 cm. Diameter: About 2.5 mm to             3 mm. Aspect: About 10° to 30° from peduncle axis. Strength:             Moderately strong. Texture and luster: Smooth, glabrous;             moderately glossy. Color: Close to 183A.         -   Reproductive organs.—Stamens: Quantity per flower: About 60.             Filament length: About 1.5 cm. Filament color: Close to 157D             to lighter than 157D; proximally, close to 75C. Anther             shape: Double and broadly reniform; basifixed. Anther size:             About 2.5 mm by 2 mm. Anther color: Close to 150C. Pollen             amount: Scarce to moderate. Pollen color: Close to 4D to             lighter than 4D. Pistils: Quantity per flower: About five to             eight. Pistil length: About 1.2 cm. Stigma diameter: About             0.3 mm. Stigma shape: Club-shaped. Stigma color: Close to             155A. Style length: About 1.2 cm. Style color: Close to             186A. Ovary color: Close to N186D. Nectaries (transformed             petals): Quantity per flower: About eleven. Length: About             9 mm. Diameter: About 5 mm. Shape: Tubular, flattened.             Texture and luster, inner and outer surfaces: Smooth,             glabrous; slightly glossy. Color, immature, inner surface:             Close to 151D. Color, immature, outer surface: Close to             151D; spot at base, close to 152C. Color, mature, inner             surface: Close to 151B; proximally, close to 146D; with             development, proximally becoming closer to 144B. Color,             mature, outer surface: Close to 151B; proximally, close to             146D; spot at base, close to 152C; with development,             proximally becoming closer to 144B.         -   Seeds and fruits.—To date, seed and fruit development have             not been observed on plants of the new Helleborus. -   Garden performance: Plants of the new Helleborus have been observed     to have good garden performance and to tolerate rain, wind, high     temperatures about 35° C. and to be suitable for USDA Hardiness     Zones 5 through 9. -   Pathogen & pest resistance: To date, plants of the new Helleborus     have not been observed to be resistant to pathogens and pests common     to Helleborus plants. 

It is claimed:
 1. A new and distinct Helleborus plant named ‘COSEH 6000’ as illustrated and described. 